Accumulated Other Comprehensive Income (Loss) (After-tax Changes by Component) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	$ (157)	$ (4,220)	$ (4,358)
Amounts arising during the year	12	332	(94)
Reclassifications from AOCI	21	153	232
Net OCI during the year	33	4,063	138
Balance at end of year	(124)	(157)	(4,220)
Reclassification out of Accumulated Other Comprehensive Income (Loss) due to Sale of U.K, Utility Business
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications from AOCI		3,578
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	0	(1,158)	(1,425)
Amounts arising during the year	0	372	267
Reclassifications from AOCI	0	0	0
Net OCI during the year	0	1,158	267
Balance at end of year	0	0	(1,158)
Foreign Currency Translation Adjustments [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) due to Sale of U.K, Utility Business
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications from AOCI		786
Qualifying Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	1	0	(5)
Amounts arising during the year	0	(39)	(19)
Reclassifications from AOCI	2	25	24
Net OCI during the year	2	1	5
Balance at end of year	3	1	0
Qualifying Derivatives [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) due to Sale of U.K, Utility Business
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications from AOCI		15
Equity Investees AOCI [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	0	0	0
Amounts arising during the year	2	0	0
Reclassifications from AOCI	0	0	0
Net OCI during the year	2	0	0
Balance at end of year	2	0	0
Equity Investees AOCI [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) due to Sale of U.K, Utility Business
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications from AOCI		0
Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	(6)	(16)	(18)
Amounts arising during the year	(1)	0	(1)
Reclassifications from AOCI	2	2	3
Net OCI during the year	1	10	2
Balance at end of year	(5)	(6)	(16)
Prior Service Costs [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) due to Sale of U.K, Utility Business
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications from AOCI		8
Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of year	(152)	(3,046)	(2,910)
Amounts arising during the year	11	(1)	(341)
Reclassifications from AOCI	17	126	205
Net OCI during the year	28	2,894	(136)
Balance at end of year	$ (124)	(152)	$ (3,046)
Defined Benefit Plans Actuarial Gain (Loss) [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) due to Sale of U.K, Utility Business
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications from AOCI		$ 2,769